<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <button>点击 </button>
</body>
<script>
  document.querySelector('button').addEventListener('click', liu(() => {
    console.log(1);
  }, 2000))
  function liu(fun, wait) {
    let timer = 0
    return function () {
      let nowTime = +new Date()
      if (nowTime - timer > wait) {
        timer = nowTime
        fun()
      }
    }
  }
  // function dou(fun, wait) {
  //   let timer = null
  //   return function () {
  //     if (timer) clearTimeout(timer)
  //     timer = setTimeout(fun, wait)
  //   }
  // }
</script>

</html>